It is well known that highway accidents are a significant cause of accidental deaths, and that a substantial cause of such accidents is excessive vehicular speed. In the past many devices have been proposed for keeping vehicular speed within posted limits. One such device comprised a manually adjustable indicator connected to the dashboard speedometer. This indicator could be pre-set by the driver for any desired speed. In accordance with one aspect of its intended use, the driver would set the indicator to the speed limit posted on the highway on which he is driving. If the speed of his vehicle exceeded the pre-set speed, a buzzer would sound alerting the driver to the fact that his vehicular speed was excessive.
Though manually adjustable indicators of the type described met with some success, they also suffered from certain drawbacks. One such drawback was that the driver would repeatedly have to adjust the indicator each time he travelled on a highway with a different speed limit in order for the device to be constantly effective. Many drivers found the need to repeatedly reset the device extremely inconvenient, and after a while some simply pre-set the indicator to the highest posted speed, thereby rendering the device ineffectual for a substantial amount of travel. Other drivers, when the need arose, simply pre-set the indicator at or near the maximum indicated on their dashboard speedometer, thereby rendering the device virtually useless as a vehicle speed alarm.
It is an object of the present invention to provide an improved vehicle speed alarm which does not suffer from the foregoing drawbacks. It is a further object of the invention to provide an improved vehicle speed alarm which does not have to be pre-set for each posted speed limit, and which can not readily be rendered useless by the driver as was the case with prior art devices of the type hereinbefore described.